The Secret Life of Beans

babyvegetablesBEANS005Beans are among the easiest of crops to grow, especially in the arid West. No bean likes to sit in watery soil. And all like warmth. Many derived from North America and we can claim them as our own. It’s hard to imagine a more widely grown crop that has sustained humans. Perhaps most importantly, beans are among the easiest crops to save seeds and pass them along to friends, family and the next generation.

That’s exactly what our ancestors have bequeathed to us: beans are self-pollinating and nearly always replicate the previous generation. The pollen sifts onto the bean flower ovary before it opens to pollinators. Most importantly, this self-pollination appears to have no deleterious effect. Beans remain vigorous from year to year without the need for cross-pollination.

And there are so many kinds! I have an Irish friend who grows fava beans, a native of North Africa but beloved in Europe, too. I grow Scarlet Runner beans, with red blossoms beloved by hummingbirds. I save the seeds at the end of each summer and plant them year after year. All the lovely, thin haricot green beans, kidney and pinto beans originated from the Americas and feed people around the world. But there’s a characteristic about beans that truly is remarkable.

Sometime in the distant past, the legume family, which includes beans, alfalfa, vetches and peas, developed a capacity to take nitrogen from the air and transfer it to their roots. On the roots are nodules that, in conjunction with common bacteria in the soil, produce the nitrogen in such a way that it fertilizes the plant. Beans and other legumes can produce the nitrogen they need to grow vigorously. And, they will enrich the soil around them with nitrogen, too. This is the basis for planting legume cover crops that serve as a natural fertilizer for organic gardeners.

All beans do have a few basic needs, although they don’t ask for much. They like warm soil, occasional moisture but not too much. Water them too much or place them in cold soil and they will rot. But grant them warm soil without over-watering and they will reward you with abundance. True, there is bean rust and bean beetles. Of all the things that ruin beans, perhaps the beetles are the worst. They can be prevented with floating row cover. Taking all these into considerations, beans are among the easiest and most varied crops you will grow.

Pole beans will be indeterminate, crawling up a trellis, studded with tiny bean flowers. Bush beans are determinate; they will conform to a tidy bush and not get too big. For gardeners who have planted both indeterminate and determinate tomatoes, the similarities are obvious. Like tomatoes, the pole beans will produce over a long period of time. They are closest to nature’s original beans. Like determinate tomatoes, bush beans will produce beans within a week or so and must be replanted every couple of weeks for a continuous harvest.

Beans are the hard workers of the garden world, delivering a huge harvest without a few short weeks. As they grow tattered and worn, yank them out. But make sure you’ve staggered the planting with another kind of bean. By the summer’s end, you’ll have harvest three or four kind of beans within a few months.

A friend called concerned that earwigs were eating her green beans. “They’re biting the leaves off, just leaving the stem,” she wailed. A thought rose from my dim memory. “I think that’s a genetic oddity,” I told her, “but let me check this out.” So I did. And it’s neither earwigs nor a genetic oddity. It’s something far odder, called a snakehead. When a bean is cracked, the coating around the interior of the bean doesn’t separate like a book to allow the stem and leaves to emerge. Instead, the stem and leaves try to emerge from the cracked opening, tearing off the leaves and sending up a stem without leaves. Chances are the plant will not recuperate. I’ve seen this often, usually it’s only a few beans in a sea of healthy specimens, but a number of leafless stems indicates the beans were cracked long before they were placed into the ground.

To plant beans, choose a sunny location. If you have alkaline soil, as most of us have in Colorado, add compost. Most beans prefer slightly acid soil, although most will soldier through. Still, adding compost that is mostly grass clippings and leaves will neutralize the soil. You need not add high nitrogen compost since beans will produce their own.

Plant each bean about one inch deep—about the depth of your first knuckle. Water them in but don’t give them the same amount of water you would give to lettuces or tomatoes. Given the right temperature, they will germinate quickly, sending up broad leaves and a sturdy stem.

Pick green beans when they are thin and tender. Shell beans are picked with the beans begin to bulge and dried beans are picked with the shell has thinned, turning brown and leathery. Once you’ve tried even one pole beans, consider experimenting with new beans each year. There’s so much variety in the Phaseolus vulgaris pea and bean family, you’re sure to find more that you’ll love.